Hoisting winch for lifting and lowering

Abstract

In a hoisting winch, a winding drum is arranged in an outer peripheral portion of a motor portion, a braking unit and an encoder are arranged on one end side of a rotor axis of the motor portion, an internal gear is fitted to an inner diameter area of the winding drum, a reduction mechanism in which planet gears are arranged between a sun gear and the internal gear is provided, the reduction mechanism, the braking unit, and the encoder are arranged in a coaxial fashion, and a wire rope fitting groove is provided on the winding drum on the braking unit side.

What is claimed is: 
     
       1. A hoisting winch comprising: a first supporting member and a second supporting member positioned to oppose each other;   a motor member including: a motor portion whose one end is supported by said first supporting member; and   a rotor which is installed into an inner diameter area of said motor portion and supported rotatably by both ends of said motor portion,     one end side of a rotor axle of said rotor being protruded from said first supporting member, and the other end side of said rotor axle being provided with a sun gear;   a cylindrical winding drum arranged on an outer periphery of said motor portion and on which a wire rope for lifting and lowering a hoist load is wound, both ends of said winding drum being supported rotatably against said first supporting member and said second supporting member, and said winding drum includes a fitting groove for fitting one end of said wire rope on said winding drum;   a reduction mechanism having an internal gear fitted onto an inner peripheral area of said winding drum, and planet gears arranged between said internal gear and said sun gear;   a braking means inserted onto said rotor axle projected from said first supporting member, wherein said braking means is supported by said first supporting member, and a center portion of said braking means being coupled to said rotor axle; and   an encoder attached to said one end of the protruding rotor axle to count a number of revolutions of said rotor axle of said motor portion.   
     
     
       2. A hoisting winch according to claim 1, wherein said reduction mechanism is constructed as a two-stage reduction mechanism which comprises: a first stage internal gear and a second stage internal gear which are fitted in parallel to said inner peripheral area of said winding drum;   first stage planet gears which are arranged between said first stage internal gear and said sun gear provided to said other end side of said rotor axle;   a first gear platform supporting rotation axles of said first stage planet gears;   a second sun gear placed at a center position of said second stage internal gear and provided at said first gear platform;   second stage planet gears arranged between said second sun gear and said second stage internal gear; and   a second gear platform to which rotation axles of said second stage planet gears are attached and which is supported by said second supporting member.   
     
     
       3. A hoisting winch according to claim 2, wherein said sun gear provided to said other end side of said rotor axle, said first stage planet gears which engage with said sun gear, and said first stage internal gear fitted on said other end side inner peripheral area of said winding drum are formed of a helical gear respectively, and a helix angle of said helical gear is set to cause a thrust force for thrusting said winding drum when a tension of said wire rope wound on said winding drum is applied. 
     
     
       4. A hoisting winch according to claim 2, wherein said sun gear provided to said other end side of said rotor axle, said first stage planet gears which engage with said sun gear, and said first stage internal gear fitted on said other end side inner peripheral area of said winding drum are formed of a helical gear respectively. 
     
     
       5. A hoisting winch according to claim 1, wherein said planet gears which engage with said sun gear provided at said other end side of said rotor axle are composed of at least three gears, and an angular interval between neighboring planet gears along a circumference direction is set not to exceed 180 degrees. 
     
     
       6. A hoisting winch according to claim 1, wherein said internal gear of said reduction mechanism is formed integrally with said winding drum.